How to repair leather supports on a sling chair?

Question

Thirty years ago, I bought some chairs that are still my favorites, but they are in need of repair. The chair's supporting structure consists of a canvas sling that hangs from a bent wood frame. A large leather cushion fastens into the sling. I found a picture of a chair with essentially the same supporting structure (the cushion, not shown, is different, but the chair is probably from the same manufacturer). The supporting structure looks basically like this:

^{Source: RetroAppeal}

The sling is a canvas "bucket". The four corners of the wooden frame hold metal hanger loops. Each corner of the sling has a heavy leather support that wraps around the metal hanger loop and is sewn to the sling. Here's a close-up of one such corner:

That picture is actually from a matching foot stool, which doesn't get any stress. So that leather is still in good condition. On the chairs, the leather got stretched and cracked where it was puilled against the metal hanger loop, and the leather started to tear at the edges (sorry, no pictures of the damage, but it is easy to visualize what happens to the leather supports when you try to pull the metal hanger loops through them).

The sling corners are two layers of heavy leather (i.e., wrapped top and bottom), over several layers of heavy canvas. The right way to fix it would be to replace the leather corners. I don't have the tools or ability to do that, and don't have ready access to any kind of shop that could do it for me. Even if I could locate such a shop, the repair would not be cost effective.

The corners are heavy-duty materials under a lot of stress. The leather is stretched and has surface cracks. On many loops, about 10% of the width has torn. Once it starts to tear, the leather quickly loses strength, and fails.

Is there a way to leave the leather corners in place and repair them that would have strength and durability similar to the original construction?

I came up with a solution that I'll share as an answer in case anyone else runs into a similar situation. But I would also welcome any other solutions readers may have.

Answer 1

The solution I came up with was to leave the leather in place and cover it with something equally strong and durable to handle the stress and wear and tear. I used strong cotton webbing that is available in various colors, with the same width as the inside of the metal loop.

The webbing wraps around the loop and extends the full length of the leather, top and bottom, to provide a lot of surface area. I used E-6000 adhesive to glue the webbing to the leather, with lots of clamping to ensure it tightly conformed to the shape. A cross section of the repaired corner looks like this (not to scale):

I saturated the bulging portion around the metal hanger (complete circumference), with CA glue (low-viscosity super glue). It soaks through, absorbs, and hardens quickly in contact with cotton, creating a hard, rigid, really tough tube around the loop (without changing the appearance of the webbing). This won't tear or break from the stress. The rest of the webbing provides a lot of surface area for glueing, with the stress going in the direction that the glue joint is the strongest.

This is a picture of a repaired corner. Black was the best webbing color I was able to access on short notice. Very little of the webbing is visible when the cushion is in place. I repaired all of the corners so they matched.